Rare earth magnets are strong magnets, and are therefore used extensively in many products. Some of the characteristics of rare earth magnets, however, include a propensity for corrosion and brittleness. Therefore, many manufacturers cover surfaces of rare earth magnets with protective coatings. The protective coatings often include nickel due to nickel's high corrosion resistance. Typically, the magnets are encased within layers of nickel and copper.
It has been observed, however, that these nickel-containing coatings can release certain amounts of nickel when exposed to moisture. This can be a problem in consumer products that have magnets that can come into contact with a person's skin since nickel can elicit allergic skin reactions in some people. Thus, some of these protective coatings should be avoided when coating magnets used as fastening elements in wearable products such as bracelets, necklaces, watches, brooches and other jewelry, where a user's skin may be in contact with the fastening elements for prolonged time periods. What are needed therefore are coatings for magnets that reduce or prevent the release of nickel or other skin irritants to levels appropriate for wearable products.